1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * MEN 14F021P00 Board Management Controller (BMC) LEDs Driver.
4 *
5 * This is the core LED driver of the MEN 14F021P00 BMC.
6 * There are four LEDs available which can be switched on and off.
7 * STATUS LED, HOT SWAP LED, USER LED 1, USER LED 2
8 *
9 * Copyright (C) 2014 MEN Mikro Elektronik Nuernberg GmbH
10 */
11
12 #include <linux/module.h>
13 #include <linux/kernel.h>
14 #include <linux/platform_device.h>
15 #include <linux/leds.h>
16 #include <linux/i2c.h>
17
18 #define BMC_CMD_LED_GET_SET 0xA0
19 #define BMC_BIT_LED_STATUS BIT(0)
20 #define BMC_BIT_LED_HOTSWAP BIT(1)
21 #define BMC_BIT_LED_USER1 BIT(2)
22 #define BMC_BIT_LED_USER2 BIT(3)
23
24 struct menf21bmc_led {
25 struct led_classdev cdev;
26 u8 led_bit;
27 const char *name;
28 struct i2c_client *i2c_client;
29 };
30
31 static struct menf21bmc_led leds[] = {
32 {
33 .name = "menf21bmc:led_status",
34 .led_bit = BMC_BIT_LED_STATUS,
35 },
36 {
37 .name = "menf21bmc:led_hotswap",
38 .led_bit = BMC_BIT_LED_HOTSWAP,
39 },
40 {
41 .name = "menf21bmc:led_user1",
42 .led_bit = BMC_BIT_LED_USER1,
43 },
44 {
45 .name = "menf21bmc:led_user2",
46 .led_bit = BMC_BIT_LED_USER2,
47 }
48 };
49
50 static DEFINE_MUTEX(led_lock);
51
52 static void
menf21bmc_led_set(struct led_classdev * led_cdev,enum led_brightness value)53 menf21bmc_led_set(struct led_classdev *led_cdev, enum led_brightness value)
54 {
55 int led_val;
56 struct menf21bmc_led *led = container_of(led_cdev,
57 struct menf21bmc_led, cdev);
58
59 mutex_lock(&led_lock);
60 led_val = i2c_smbus_read_byte_data(led->i2c_client,
61 BMC_CMD_LED_GET_SET);
62 if (led_val < 0)
63 goto err_out;
64
65 if (value == LED_OFF)
66 led_val &= ~led->led_bit;
67 else
68 led_val |= led->led_bit;
69
70 i2c_smbus_write_byte_data(led->i2c_client,
71 BMC_CMD_LED_GET_SET, led_val);
72 err_out:
73 mutex_unlock(&led_lock);
74 }
75
menf21bmc_led_probe(struct platform_device * pdev)76 static int menf21bmc_led_probe(struct platform_device *pdev)
77 {
78 int i;
79 int ret;
80 struct i2c_client *i2c_client = to_i2c_client(pdev->dev.parent);
81
82 for (i = 0; i < ARRAY_SIZE(leds); i++) {
83 leds[i].cdev.name = leds[i].name;
84 leds[i].cdev.brightness_set = menf21bmc_led_set;
85 leds[i].i2c_client = i2c_client;
86 ret = devm_led_classdev_register(&pdev->dev, &leds[i].cdev);
87 if (ret < 0) {
88 dev_err(&pdev->dev, "failed to register LED device\n");
89 return ret;
90 }
91 }
92 dev_info(&pdev->dev, "MEN 140F21P00 BMC LED device enabled\n");
93
94 return 0;
95
96 }
97
98 static struct platform_driver menf21bmc_led = {
99 .probe = menf21bmc_led_probe,
100 .driver = {
101 .name = "menf21bmc_led",
102 },
103 };
104
105 module_platform_driver(menf21bmc_led);
106
107 MODULE_AUTHOR("Andreas Werner <andreas.werner@men.de>");
108 MODULE_DESCRIPTION("MEN 14F021P00 BMC led driver");
109 MODULE_LICENSE("GPL v2");
110 MODULE_ALIAS("platform:menf21bmc_led");
111